Sewing machine



Aug. 17 1926. 1,596,369

G. W. NELSON SEWING MACHINE Original Filed Ma? 17 1919 4 Sheets-Sheet 1 H ISATTORNEY Aug. 17 1926. 1,596,369

G. w. NELSON I SEWING MACHINE Original Filed May 17, 1919 4 Sheets-Sheet 2 0mm cygk-$ HIS ATTORNEY Aug. 17 1926.

1,596,369 G. w. NELSON SEWING MACHINE in l Filed May 17. 1919 4 Sheets-Sheet 5 0 INVENTOR -inW m a 5* 4 H15 ATTORNEY Aug. 17 1926.

' G. W. NELSON SEWING MACHINE 4 Sheets-Sheet 4 Original Filed May 17. 1919 IINVENTOR Q? Y M HIS ATTORNEY Patented Aug. 17, 1926. v v

UNITED] STATES I 1,596,369 PATENT OFFICE.

GEORGEW. NELSON, 0F CLEVELAND, OHIO, ASSIGNOR TO THE STANDARD MG I MACHINE COMPANY, OF CLEVELAND, OHIO, A CORPORATION OF OKIQ SEWING MACHINE.

Original application filed May 17, 1919, Serial No. 297,857. Divided and this application fled latch 91,

1928. Serial No. 626,630.:

This invention relates to sewing machines, and particularly to chain-stitch sew ng machines of the type adapted for forming successive groups or series of stitches, such, for example, as that disclosed in Letters Patent No. 1,252,931, granted to me January 8, 1918. In this type of machine it is customary to break or sever the thread on the completion of a group of stitches by suitable means under the control of the operator, and it has therefore been found desirable that provision should be made for certain necessary manipulation of the thread, to wit: that means be employed for pulling off from the source of supply a sufiicient length of thread to permit the forming of the first stitch of a series without drawing down the end of the thread below the upper surface of the work, and that the length of the thread beyond the needle eye at the beginning of the making of such a series of stitches should be determined in order that theremay be no substantial excess thread beyond what is necessary for the formation of the first stitch. Means for effecting such manipulation of the thread are disclosed in my aforesaid Patent No. 1,252,931, and comprise a thread-restraining device or threadclamp for clamping the thread upon the completion of a series of stitches, and a pullofi' device for drawing off from the source of supply a sufficient length of thread for the first stitch of a new series; these threadrestraining and pull-oil devices being automatically operated in the performance of their functions after one series of stitches has been completed and the action of the needle-bar mechanism is substantially finished and before the next series is started. The object of my present invention is to provide an improved means for effecting such automatic operation of said thread-restraining and pull-0E devices. This object I attain by the novel arrangement and combination of parts hereinafter described and claimed.

' Referring now to the accompanying drawings in which I have shown only so much of a sewing machine as is necessary to illustrate my invention,-

Fig. 1 is a rear end elevation of a sewing machine embodying the invention, with the loose driving pulley removed and its supporting shaft in section, showing the parts in the positions the occupy durin the normal operation of t e machine an prior: to

the automatic sto ping thereof.

Fig. 2 is a simi ar view showing the parts in the positions they occupy on the automatic stopping of the mac me.

Fig. ,3 1s a rear side elevation of the machine, with the parts in positions corresponding to those in Fig. 1,

Fig. 4 is a top plan of the rear end of the machine broken away, with the parts in positions corresponding to those in Fig. 2.

Fig. 5 is a section taken on the line 5-5 of Fig. 3, but showing the parts in positions This application is a division of my ending application Serial No. 297, 857, file May 17, 1919, which is directed to an automatic stop mechanism for sewing machines, and as the invention constituting the subject-matter of the present application is directly associated with said stop mechanism for cooperation, I will first describe the latter and then follow with the description of thepresent improvements. I

The sewing machine here shown as equipped with my invention embodies a main frame comprising upper and lower portions, 2 and 3, suitably connected and adapted for the support of the various parts of the operating mechanism. Suitably journaled in the lower portion 3 of the frame is the main shaft 4, which extends lengthwise of said lower ortion 3 and from which the several operating parts of the machine are driven throulgh suitable connections in usual manner. his shaft 4 at its rear end projects beyond the adjacent end of the frame for the association therewith of the starting and stopping mechanism which will now be described.

On the outer end of the shaft 4 is a loose driving pulley 5, which is held on the shaft by means of a headed screw 6, threaded into the end of the shaft for removable connection therewithfl This driving pulle is here shown as rovided at its inner en with a projecting ub portion 7, having an annular ing pulley when the clutch is to be engaged or can be contracted from frictional engagement with said wall when the clutch is to released. This split ring 9 is carried in rotation with the shaft'4 through suitable gage the connector and determined time in the operation ofmachine-as at the conclusion of the sewing of a predetermined group of stitches-to enpositively shift the same to its clutch releasing sition. This controller 18 is here shown in the form of a lever mounted on a stationary pivot 19 on the frame of the machine for movement a plane transversely of the driving-shaft, I and as having an arm 20 adapted to be shifted, by a rocking of the controller on its sald ivot, to and from an operative osiconnections, whereby,.when it is e anded tion 1n the path of the outer end 21 o the into clutching engagement with the iving ulley, the latter, as the driving clutch memher -.will impart rotation to said splitrmg an thereby to' the connected shaft.

The connections between the shaft 4 and the. lit rin 9, as here shown, comprise 'a'co ar 10, xed to the, shaft for rotationtherewith by suitable fastening means,

such as the set screw 11, and a'connector 12, here shown in yoke form, pivotally eonnected with the collar 10 at opposite s1des thereof, as at 13, and havlng a laterally projecting wedge member 14, extendm between the oplposing end. walls 15, o the split ring 9. swinging the connector laterally in one d1rection,-its said wedge member 14 will spread. apart the engaging ends of the split r1ng9 and force or expand the latter into frictional clutching engagement i the latter will with the driving ulley, and. b sw nging the connector in t e. opposite rectlon to artially withdraw its wedge member from between the en aging ends of the spl t. rmg, become released from its fast clutching engagement with the driving pulley. It will be understood, however, that connection between the shaft and s lit rm should always be maintained so t at sa1 parts will always move in rotation together, and in order to effect this the clutch releasing movement of the connector is limited by a suitable stop, such as the shoulder 16.

see'Fig. 6), to-prevent the complete withraw'al of the'wedge member 14 from between the ends of the spllt ring.

.In the present case, the connector 1s adapted to be swung laterally in a direction to advanceits wedge member 14 into "-wedging position. between the ends of the s lit ring, whereby to effect engagement of tlie clutch members, b means of a suitable spring, "such as in icated at 17, which is seatedin-a pocket in the collar 10 wlth one and bearing against the inner side, of the connector, "as clearly shown in Fig. 6. As a means to move the. connector .against the pressure of this sprin 17 and in a direction to withdraw its we ge member from wedging position between the ends of the split ring 9, whereby to release the clutch, I.have provided a controller member 18 which is automatically operative at a preconnector 12 in its rotary movement about the axis of the driving shaft; said controller arm having an inner cam or inclined surface 22, which, upon the lowering of the controller arm to its operative position in the path of the connector arm 21, will en- '23, which acts to bring the connector and connected'shaft to a stop at a predetermined point in their rotation. This buffer is here shown as being carried by the controller and as being supported by a spring 24 seated within a chamber 25 in said controller. On the controller arm directly above said buffer is a shoulder 26 over which the laterally movable connector arm 21 rides when advancing into engagement with thebufier and ag'ainstwhich it is returned and held by the rebound of the buffer, as shown in Fig. 6.- In this way the machine is always brought to a stop with the parts thereof in the same definite predetermined positions. When it is desired to again start the machine, the controller -is rocked outwardly to a point beyond the path of the connector, as shown in ig. 1, thereby releasing said connector and permitting it to be automatically shifted under the action of the spring 17 to its wedging position for effecting engagement of the clutching members.

The controller is normally held in its out- 115 of the machine and having an up-turned 120 portion at its outer end engaging the controller within a notch 32 thereon, as shown in Fig. 1. A spring 33, located on the bolt between a collar 34 thereon and the adjacent end of the stationary bracket 31 (see Fig. 125

3), acts to yieldingly hold the bolt in its latching position until the completion of a predetermined seriesor group of stitches, at which time it is tripped automatically to release the controller and permit the latter being swung inwardly to its position for engaging the connector and shifting it to clutch-releasing position. When the controller is thus released by the latch, it is swung inwardly as described by means of a suitable spring, such as 35, which connects at one end with said controller and at its opposite end with a stationary stud 46 on the machine frame.

, The latch device may be tripped by any suitable means. Preferably the tripping means is operated fromthe main shaft 1 through a cross-shaft 37, driven from said main shaft by gearing (not shown), by means of which a relatively slow rotary movement is imparted to this cross-shaft. On the completion of a predetermined group of stitches, the cross-shaft is intended to bring into operation a releasing device. This releasing device is shown as carried by a disk 38 on the end of the cross-shaft and is in the form of a radial pin 39, slidable in and out of o erative position and suitably held in p ace. When projected into operative position as shown, it is brought, on each complete rotation of the crossshaft, into engagement with the inner end of the latch bolt 30, and moves the latter lengthwise in a direction to disengage its outer end from the notch 32 of the controller, as shown in Fig. 2, whereupon the parts will act to release the clutch in the manner previously described. A swinging plate 40 normally covers this latch tripping means.

' To start the machine following the release of the clutch as described, the controller isswung from its operative or connector-engaging position, shown in Fig. 2, to its inoperative or connector-releasing position, shown in Fig. 1, in which latter position it is caught and held by the latch 30. This movement of the controller to its inoperative position is ada ted to be effected by manually operate means. Such means as here shown comprises a lever 45 fulcrumed on the stationary stud 46 and arranged with one arm 47 extending beneath an arm 48 of the controller for engagement therewith, and its other arm 49 extending to a suitable position for connection with the treadle (not shown), or

. other similar operating device.

When the controller 18 is operated to shift the connector to clutch-releasing. osition, saidconnector, as heretofore described, continues its rotation a short distance under the momentum of the driving shaft until it is brought to .a stop by contact with the buffer 23. As this momentum is very considerable when the machine is being oper- -'ated at high s eed, it may be desirable to employ a suita le braking device that will be operative to come into action immediate- 1y upon the release of the clutch and so retard the speed of the machine before contact of the connector arm 21 with the buffer 23 as to prevent injurious jar or strain on the parts when such contact takes place. The braking device here employed for such purpose comprises a brake band 50 which cooperates with the collar 10' on the drive shaft adjacent its inner end (see Figs. 4, 5 and 6) in the manner fully described in the original application of which this is a division.

The sewing machine here illustrated, is, as before stated, a chain-stitch sewing machine of the type adapted for forming successive groups or series of stitches. In this type of machine it is customary to break or sever the thread on the completion of a group of stitches by suitable means under the control of the operator, and it has therefore been found desirable that provision should be made for certain necessary manipulation of the thread, to wit: that means be employed for pulling off from the source of supply a sufficient length of thread to permit the forming of the first stitch of a series without drawing down the end of the thread below the upper surface of the work, and that the length of the thread beyond the needle eye at the beginning of the making of such a series of stitches should be determined in order that there may be no substantial excess thread beyond what is necessary for the formation of the first stitch. Means for effecting such manipulation of the thread are disclosed in my aforesaid Patent No. 1,252,931, and comprise a thread-restraining device or threadclam for clamping the thread upon the comp etion of a series of stitches, and a pull-ofi device for drawin off from the source of supply a sufficient length of thread for the first stitch of anew series; these thread-restraining and pull-ofl' devices being automatica 1y operated in the performance of their functions after one series of stitches has been completed and the action of the needle-bar mechanism is substantially finished and before the next series is started.

The thread-clamp and pull-off devices here shown are of the same construction and operation as those of my aforesaid patent; the-thread-clamp, indicated at a, being located on the face-plate of the machine and comprising fixed and movable clamping jaws, 60 and 61, between which the thread t is led in its passage from the thread supply to the needle, and the pull-off, indicated at 7), being located on the upper part of the arm or frame for engagin the thread between the'thread supply an said clamp and being inthe form of anangle lever having an up-turned thread-engaging finger 62.

These thread-clamps and pull-ofi' devices.

re"tly controlled by. a single controlling member in the form of a rod 63 mounted to slide in suitable guide-ways on the arm of the machine, such as indicated at (34, 65 and 66, and having operative connection with said devices, whereby, upon movement of the rod 63 in a forward direction, it will operate the thread-clamp to clamp the thread and thereafter operate the pull-oft to pull a predetermined length of thread from the spool or other source of supply to provide for the formation of the first stitch of a new series. A reverse movement of the rod will cause said devices to assume their normal positions, i. e. the thread-clamp in open or unclamping position, and the pull-off back from the normal path of the thread.

In accordance with my present invention, I have provided an improved means for automatically controlling the action of the rod 63 and associated parts from the automatic stop mechanism hereinbefore described. This means, as here shown, embodies a main actuator, in the form of a cam on the collar 10 carried by the main drive-shaft, and -a transmitter for imparting movement to the rod 63 and associated parts from said actuator 70, which includes an elbow lever 71 pivoted to a bracket 72 on the machine frame with one arm in a position for engaging the rear end of the rod 63, and a rod 73 pivoted to the other arm of said elbow lever and depending therefrom to be engaged at its lower end at predetermined times by the actuator cam 70. This transmitter rod 73 adjacent to its lower end passes through a guide slot 74 inv a bracket stud 75 on the machine frame, which slot extends transversely of the cam 70, as clearly shown in Fig. 4. In the operation of the machine, as when sewing a group of stitches the rod 73 is held by a spring 76 towards the inner end of said slot and at one side of the path of the cam 70, as shown in Fig. 3, in which position it is inoperative to actuate the rod 63 and thread-controlling means associated therewith. When, however, the machine is to bebrought to'a stop by the action of the stop mechanism upon the completion of the sewing of a group of stitches,

the rod 73 is shifted by automatic controlling means to bring its lower end into the path of the cam 70, whereby it will be engaged by the latter and raised sufficiently to rock the connected elbow-lever 71 into engagement with the end of the rod 63 and impart the necessary longitudinal movement to the latter to operate the threadclamp and pull-off devices in the manner hereinbefore described. The cam 70 is so timed as to impart the described operative upward stroke to the rod 7 3, just prior to the stopping of the machine, as will be clear by reference to Fig. 5, which shows the parts in position with the machine stopped and with the rod 73 resting on the high partof the cam 70.

As a means for so shifting the rod 73 to position for engagement by the cam 70, the

controller 18 is provided with a second arm 78 at the inner side of its clutch-controlling arm 20, which is provided with a cam or inclined surface 79 adapted, upon the swinging of the controller 18 to clutch-releasing position, to be brought into engagement with the lower end of the rod 73 and force it laterally to its operative position in the .ath of the cam 70, as shown in Fig. 4. pon the backward or outward movement of the controller for permitting engagement of the clutch, its arm 7 8 will thereby be withdrawn from engagement with the rod 73, as shown in Fig. 1, whereupon said rod will be moved laterally to its inoperative position under the action of the spring 76, and the rod 63 will be permitted to be returned to its normal or inoperative position under the action of a suitable spring, such as the spring 80, interposed between the stationary lug 65 and a block 81 on said rod.

To review the operation of the invention briefly, if the machine is running, the latch 30 will be operated upon the completion of a predetermined group of stitches, by the tripping device 39, to release the controller 1.8, whereupon the latter will be. rocked under the action of the spring 35 to swing its cam arms 20 and 78 into position to engage, respectively, with the connector-arm 21 and the rod 73, the engagement. with the connector operating to shift the latter for effecting release of the clutch, and the engagement with the rod 73 operating to shift the latter for effecting the operation of the thread-clamp and pull-ofi' devices. To restart the machine for the sewing of the next group of stitches, the controller 18 is swung outwardly by the lever 45 to disengage its armsfrom the said connector-arm 21 and rod 73, whereupon the connector will be automatically operated by the spring 1.7 to effect engagement of the clutch, and the rod 73 will be shifted to its inoperative position to permit the thread-clamp and pull-ofi' devices to reassume their normal positions.

I want it to be understood that the present im rovements relating to the automatic contro of the thread-clamp and pull-off devires may be employed in combination with stop mechanisms differing substantially from that here shown and described, without departure from the invention as pointed out in the following claims.

What I claim is 1. In a sewing machine and in combination, means for forming successive groups of stitches said means including a shaft, a

thread-controlling means from said actuator, means yieldingly holding said transmitter in inoperative position relative to the actuator during the sewing of a group of stitches, and means operative upon the completion of a group of stitches for positively shifting the transmitter to operative position for engagement by its said actuator and for rendering the clutch ineflective.

2. In a sewing machine and in combination, means for forming successive groups of stitches said means including a shaft, a driving clutch for said shaft, a clutchreleasing device, a thread-controlling means, an actuator therefor carried by the said -shaft, a transmitter for imparting movement to the thread-controlling means from said actuator and being supported in inoperative position relative to the latter during the sewing of a group of stitches, and a twoarmed controller automatically movable upon the completion of a group of stitches to a position whereby one of its arms will shift the transmitter to operative position for engagement by its said actua-tor and the' other arm will efi'ect a release of the clutch.

13. In a sewing machine and in combination, means'for forming successive groups of stitches, a thread-controlling means, an actuator therefor, a transmitter for imparting movement to the thread-controlling means from said actuator, means yieldingly holding said transmitter in inoperative position relative to the actuator during the sewing'of a group of stitches, and a controller automatically operative upon the completion of. a group of stitches to shift the transmitter to operative position for engagement by its said actuator.

4C. In a sewing machine and in-combination, means tor forming successive groups of stitches, a thread-controlling means, an actuator therefor, a transmitter for imparting .movement to the thread-controlling means from said actuator, means yieldingly holding said transmitter in inoperative position relative to the actuator during the sewing of a group of stitches, and a controller cam automatically operative upon the completion of a group of stitches to shift the transmitter to operative position for engagement by its said actuator.

5. In a sewing machine and in combination, means for forming successive groups of stitches, a thread-controlling means, an actuator therefor, a transmitter for imparting movement to the thread-controlling means from said actuator, means yieldingly holding said transmitter in inoperative position relative to the actuator during the sewing of a group of stitches, and a pivoted controller cam automatically operative upon the completion of a group .of stitches to shift the transmitter to operative position for engagement by its said actuator.

GEORGE w. NELSON. 

